Electronic Device for Synchronizing Tasks of an Electronic Appliance

ABSTRACT

An electronic device can be used for synchronizing tasks of an appliance that includes a memory access controller having inputs associated with priority levels. The device includes control circuits configured for receiving signals from events and delivering in response signals for activation of tasks. A configurable interface for external events designed to receive first event signals from at least one circuit of the appliance and to route some of them to the corresponding control circuits as a function of a first law of correspondence. A configurable interface for internal events designed to receive second event signals corresponding to the signals for activation of tasks and to route some of them to the control circuits as a function of a second law of correspondence.

This application claims priority to French Patent Application No.1553064, filed on Apr. 9, 2015, which application is hereby incorporatedherein by reference.

TECHNICAL FIELD

Various embodiments of the invention relate to an electronic devicedesigned to synchronize tasks of an electronic appliance.

BACKGROUND

Electronic appliances generally comprise a plurality of integratedcircuits alternately processing data circulating within the electronicappliance and stored before and after the processing by one of theintegrated circuits within an area of the, or of a, main memory of theelectronic appliance.

In order to control the accesses to the memory of the various electroniccircuits, an electronic appliance generally comprises a memory accesscontroller or descriptor, also known under the acronym DMA (for DirectMemory Access). The memory access controller allows the direct controlof the transfer of data between a peripheral device and a memory,irrespective of the direction of the transfer, without the interventionof a microprocessor except for launching and concluding the transfer.

A memory access controller thus avoids locking up, in other wordsrendering unavailable, the microprocessor during the execution ofcertain tasks of the various integrated circuits.

An electronic appliance comprising a memory access controller generallyoperates with the aid of a software application implementing a timingdelay allowing the sequencing of the execution of the various tasks tobe carried out by the integrated circuits.

In such a system, in order to be sure of activating each of the tasks ata time when the data are accessible and in the desired form, the timedelay is generally maximized. In fact, the execution of a task is oftentriggered while the data to be processed by the integrated circuit forthe task have already been available for some time.

Such a sequencing limits the speed of processing of the data and byconsequently limits the usage capacities of an electronic system.

Such a system notably has a processing speed, and hence a performance,which is too slow to allow a use for data having to be processed on thefly, such as in the case of video applications, notably for “streaming”applications.

SUMMARY

Various embodiments of the invention relate to the management of thetasks of various integrated circuits of the same electronic appliance,and more particularly the time management and the sequencing of thesetasks

According to one embodiment, a device is provided for synchronization ofthe tasks of integrated circuits coupled, for at least some of them, toa memory access controller so as to allow the processing of data on thefly using an electronic architecture.

According to one aspect, an electronic device designed to synchronizetasks of an electronic appliance comprising at least one circuit and amemory access controller having inputs each associated with a prioritylevel. The device comprises at least two control circuits configured forreceiving signals from events and for delivering in response signals foractivation of tasks. A configurable interface for external events isdesigned to receive first event signals from at least one circuit of theelectronic appliance and to route at least some of these first eventsignals to the corresponding control circuits as a function of a firstlaw of correspondence. A configurable interface for internal events isdesigned to receive second signals from events corresponding to thesignals for activation of tasks delivered by the control circuits and toroute at least some of them to the control circuits as a function of asecond law of correspondence. The outputs from the control circuits aredesigned to be connected to the inputs of the memory access controllerdepending on the desired priority level for the tasks associated withthe signals for activation of tasks delivered by each of the controlcircuits.

Such a device may correspond to an electronic device for controlling thepath to be followed by the data, or Hardware Datapath Manager. Thedevice is thus designed and configured for receiving the various eventsfrom the electronic appliance, notably relating to the completion oftasks, and for controlling the execution of a task following thecompletion of a preceding task without any latency time due to a timingdelay.

The device more particularly allows the various circuits of theelectronic appliance, and notably the integrated circuits coupled to thememory access controller, to be informed of the time when the datarequired for the execution of one of their tasks becomes available andto instruct the direct access controller to give immediate access tothis data in memory.

Advantageously, the device may furthermore comprise an input interfaceconfigured for transmitting signals for activation of tasks generated byintegrated circuits coupled to the memory access controller via thedevice to at least one of the control circuits, the at least one controlcircuit having a first mode of operation in which the control circuittransmits the signal for activation of tasks received upon reception ofa first or second event signal, the integrated circuits being coupled toat least one of the control circuits via the input interface dependingon the desired priority level for the tasks associated with the signalsfor activation of tasks delivered by the integrated circuits.

The input interface thus allows signals for activation of tasksgenerated by the integrated circuits to be transmitted to the memoryaccess controller via the control circuits, directly or else followingthe reception of a first or second event signal depending on the mode ofoperation of the control circuit.

The first mode of operation, or filtering mode, is used for controllingthe time at which the access to the memory access controller is given toan integrated circuit. It allows the tasks of the various integratedcircuits to be synchronized.

More precisely, the filtering mode allows the transmission of a taskactivation signal by the control circuit in question to be triggered atthe moment when a first or second event signal is received by thecontrol circuit, the task activation signal corresponding to thatdelivered by an integrated circuit to the control circuit in questionvia the input interface.

The at least one control circuit may have a second mode of operation inwhich the control circuit generates and delivers a task activationsignal upon reception of a first or second event signal.

The second mode of operation, or emulation mode, allows the activationof a task to be controlled by internal generation, by the controlcircuit, of a task activation signal, in other words without havingreceived on the input interface a task activation signal coming from anintegrated circuit.

In other words, the emulation mode allows the control of the transfer tothe memory access controller of an event coming from the system in otherwords which does not originate from one of the integrated circuits, suchas for example an event generated by an interrupt. The control circuitthus emulates the transmission of an event by an integrated circuit tothe memory access controller. It emulates an integrated circuit thatwould need a transfer of data.

The incorporation of the emulation mode allows correspondingly moretasks operating within the electronic appliance to be synchronized.

The at least one control circuit may also exhibit a third mode ofoperation in which the control circuit operates as a simple electricalconnector.

The third mode of operation, or “by-pass” mode, is a default mode, inwhich the control circuit is “transparent”. This mode may be used forcontrolling the events received by the control circuit or else forgenerating events to the rest of the device or else to another controlcircuit.

Preferably, the at least one control circuit comprises an operationalmode selector able to switch the operation of the control circuitbetween the first, the second and the third mode of operation.

The device may advantageously furthermore comprise at least oneadditional control circuit configured for receiving the first and secondevent signals, the at least one additional control circuit having afirst mode of operation in which the at least one additional controlcircuit transforms the first or second event signal received into acorresponding task activation signal and delivers it via an output to acircuit of the electronic appliance without going via the outputinterface.

The device can thus, by virtue of the additional control circuit,control the circuits of the electronic appliance which require a startsignal and notably those not communicating with the memory accesscontroller.

The interface for external events allows the events to be received fromsuch circuits, notably relating to the completion of tasks, and thus tocontrol the circuits of the electronic appliance not communicating, ornot communicating all the time, with the memory access controller inorder to synchronize the tasks of all the circuits.

Preferably, the at least one additional control circuit also comprises amodule for receiving a signal confirming reception of the taskactivation signal, or “acknowledge signal”, the reception module beingconfigured for detecting the reception at the input of the additionalcontrol circuit of the event corresponding to the task activation signalpreviously generated by the additional control circuit.

The reception module thus allows it to be verified that the circuitcoupled to the output of the additional control circuit has indeedreceived the activation signal. This module thus allows a receptionverification function, referred to as “handshaking,” to be emulated.

The additional control circuit thus has the property of cumulatingrequests for activation of tasks in order to send them to a circuit ofthe electronic appliance which could not manage the cumulation of therequests when the request can be accepted. The additional controlcircuit allows a circuit of the appliance to be de-synchronized from therest of the system without however losing the synchronization of thetasks of the appliance.

Advantageously, the at least one additional control circuit can have asecond mode of operation in which the additional control circuitoperates as a simple electrical connector.

The second mode of operation of the additional control circuit allowsthe event selected at the input of the additional control circuit to bedirectly routed to the output of the additional control circuit withoutmodifying the signal. This second mode can be used for the detection oferrors given that the events received may be observed and monitoredduring their passage through the additional control circuit, and that acomparison may be made between the event received and that transmittedby the additional control circuit.

Preferably, the at least one additional control circuit comprises anoperational mode selector capable of switching the operation of theadditional control circuit between the first mode of operation and asecond mode of operation.

According to another aspect, an electronic appliance is providedcomprising an electronic device such as defined hereinabove.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages and features of the invention will become apparent uponexamining the detailed description of one non-limiting embodiment of theinvention and of the appended drawing, in which the single figure showsschematically an electronic device for synchronization of tasks of anelectronic appliance according to one embodiment of the invention.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The electronic appliance APP comprises an electronic device 1 forsynchronization of the tasks coupled to a main memory 2 via a memoryaccess controller 3. The electronic appliance APP furthermore comprisesintegrated circuits IP1 and IP2 each comprising an output for activationof tasks S coupled to the memory access controller 3 via the device 1.The outputs for activation of tasks S are configured for deliveringsignals for activation and control of data streams from the memoryaccess controller 3.

The memory access controller 3 has several inputs a, b, c associatedwith different priority levels.

The electronic device for synchronization of tasks 1 comprises an inputinterface 4 comprising, in the embodiment illustrated, two inputs E14and E24 coupled to the output S of the various integrated circuits IP1and IP2. The input interface 4 is configured for receiving and fortransmitting via two outputs S14 and S24 signals for activation of tasksgenerated by the integrated circuits IP1, IP2. The two outputs S14 andS24 are each connected to one of the two inputs E14, E24 of the inputinterface.

The device 1 furthermore comprises a configurable interface for externalevents 5, comprising a first bus input E35 able to receive first eventsignals generated by other circuits 12 of the electronic appliance APP.The bus connected to the first input E35 allows the signals from thecircuits 12 of the electronic appliance APP to be assembled andre-synchronized.

The device 1 also comprises, in this embodiment, three control circuits6 a, 6 b, 6 c configured for delivering signals for activation of tasks.The three control circuits 6 a, 6 b and 6 c each comprise a first and asecond event input, respectively referenced E1 and E2, and an output S1designed to deliver task activation signals.

The interface for external events 5 comprises three outputs S15, S25,S35 respectively coupled to the first input E1 of the three controlcircuits 6 a, 6 b, 6 c. The interface for external events 5 thuscomprises an output S15, S25, S35 for each control circuit 6 a, 6 b, 6c. The interface for external events 5 is configured for processing thefirst event signals received by means of a first law of correspondenceand delivering certain of the first event signals to the correspondingcontrol circuits 6 a, 6 b, 6 c via the corresponding outputs S15, S25,S35.

The control circuits 6 a, 6 b, 6 c furthermore comprise a task inputdesigned to be coupled to an output S14, S24 of the input interface 4.In the embodiment illustrated, the task input E3 of each of the firsttwo control circuits 6 a, 6 b is coupled to a separate output,respectively E14 and E24, of the input interface 4, whereas no outputfrom the input interface 4 is coupled to the task input E3 of the thirdcontrol circuit 6 c.

The device 1 also comprises a configurable interface for internal events7 comprising three inputs E17, E27, E47 respectively coupled to theoutput S1 of the control circuits 6 a, 6 b, 6 c and outputs S17, S27,S37 respectively coupled to the second events input E2 of the controlcircuits 6 a, 6 b, 6 c. The interface for internal events 7 isconfigured for processing, by means of a second law of correspondence,the second event signals relating to events corresponding to the signalsfor activation of tasks that the interface for internal events 7 hasreceived and for delivering certain of the second event signals to atleast one of the control circuits 6 a, 6 b, 6 c.

In another embodiment, the device 1 can also comprise a software blockfor internal generation of events. This software block for internalgeneration of events thus allows a software action to be used forgenerating an event in place of a signal coming from a hardwareelectronic module. This software block for internal generation of eventsthus offers the possibility of a software/hardware management, in otherwords a cooperative management between the software modules and thehardware modules, in the case notably of a hybrid implementation.

Each control circuit 6 a, 6 b, 6 c is configured for delivering signalsfor activation of tasks.

Each control circuit 6 a, 6 b, 6 c has three modes of operation: anemulation mode, a filtering mode and a “by-pass” mode. Each controlcircuit 6 a, 6 b, 6 c furthermore comprises a operational mode selector60 allowing the operation of the control circuit 6 a, 6 b, 6 c to beswitched between the three modes of operation.

In emulation mode and the filtering mode, a control circuit 6 a, 6 b, 6c is configured to deliver them following the reception of a first orsecond event signal which may be coming from the interface for externalevents 5 or from the interface for internal events 7.

In “by-pass” mode, the control circuit 6 a, 6 b, 6 c is “transparent”,in other words the task activation signal received from the inputinterface 4 is transmitted without time delay and without modification.The control circuit 6 a, 6 b, 6 c does not therefore wait for thereception of a first or second event signal in order to transmit thetask activation signal. Moreover, in this mode, the control circuitcannot generate any task activation signals by itself upon receivingfirst or second event signals.

In filtering mode, the control circuit 6 a, 6 b, 6 c triggers thetransmission of a task activation signal delivered by the inputinterface 4 at the moment when a first or second event signal isreceived by the control circuit 6 a, 6 b, 6 c.

The filtering mode and the “by-pass” mode may be used only in the casewhere one of the inputs of the control circuit 6 a, 6 b, 6 c iselectrically connected to an output of the input interface 4, as is thecase for the first two control circuits 6A and 6 b.

In emulation mode, the control circuit 6 a, 6 b, 6 c generates anddelivers a task activation signal upon receiving first or second eventsignals.

In order to use the emulation mode the control circuit 6 a, 6 b, 6 cdoes not need to be connected to the input interface 4. The third inputcircuit 6 c of the embodiment illustrated operates in emulation mode.

The filtering and emulation modes thus allow a maximum of tasks of theelectronic appliance APP to be synchronized.

In the embodiment illustrated in the figure, the first two controlcircuits 6 a and 6 b can operate in any of the three modes, and notablythe filtering mode, and the third control circuit 6 c can only operatein emulation mode given that its third input E3 is not coupled to anoutput of the input interface 4, and more particularly an output of theinput interface connected to an input connected to an integratedcircuit.

The device 1 furthermore comprises an output interface 8 comprisinginputs E18, E28, E38 respectively connected to the output S1 of thecontrol circuits 6 a, 6 b, 6 c and outputs S18, S28, S38 connected tothe inputs E18, E28, E38. The output interface 8 is configured fortransmitting the signals for activation of tasks delivered by thecontrol circuits 6 a, 6 b, 6 c to the inputs a, b, c of the memoryaccess controller 3.

When the device 1 is installed in the electronic appliance APP, theoutputs S18, S28, S38 of the output interface 8 are electricallyconnected to the inputs a, b, c of the memory access controller 3depending on the desired priority level for the tasks associated withthe signals for activation of tasks delivered by each of the controlcircuits 6 a, 6 b, 6 c.

The cabling inside of the device 1 is fixed. Consequently, in order tointervene on the order of processing of the tasks, a user only has tochange the cabling at the input of the device 1, notably between theintegrated circuits IP1, IP2 and the input interface 4 of the device 1,and/or at the output of the device 1, notably between the outputinterface 8 of the device 1 and the memory access controller 3.

In other words, the electrical coupling between the outputs S1 of thevarious control circuits 6 a, 6 b, 6 c and the inputs E18, E28, E38 ofthe output interface 8 is fixed and unchangeable inside of the device 1,whereas the cabling between the outputs S18, S28, S38 of the outputinterface 8 and the inputs a, b, c of the memory access controller 3 isimplemented by an installer such that the signals for activation oftasks delivered by each of the control circuits 6 a, 6 b, 6 c areassociated with a given priority level, given that each input a, b, c ofthe memory access controller 3 is associated with a certain priority.

Thus, each task activation signal delivered by a control circuit 6 a, 6b, 6 c is associated with a priority level with respect to the othersignals for activation of tasks by virtue of the cabling between thecontrol circuits 6 a, 6 b, 6 c, the output interface 8 and the memoryaccess controller 3.

Similarly, each activation signal delivered by an integrated circuitIP1, IP2 to the input interface 4 is associated by a user during theinstallation with a priority level by virtue of the internal cabling ofthe device 1 between the inputs E14, E24 of the input interface 4 andthe control circuits 6 a and 6 b and of the cabling between the controlcircuits 6 a, 6 b, 6 c, the output interface 8 and the memory accesscontroller 3.

The inputs E14, E24 of the input interface 4 are therefore electricallyconnected to the integrated circuits IP1, IP2 depending on the desiredpriority level for the tasks associated with the signals for activationof tasks delivered by the integrated circuits IP1, IP2. In order tomodify the priority levels associated with the tasks, the user thereforeonly has to change the order of the cables coupled to the outputs S18,S28, S38 of the output interface 8 if he/she cannot intervene on theinputs E14, E24 of the input interface 4, or inversely to change theorder of the cables coupled to the inputs E14, E24 of the inputinterface 4 if he/she cannot intervene on the outputs 18, S28, S38 ofthe output interface 8.

The first and second laws of correspondences governing the processing ofthe first and second events by the interface for external events 5 andthe interface for internal events 7 is programmable by a user notablyduring the installation. The programming may be adapted according to thecabling implemented between the integrated circuits IP1 and IP2 and theinput interface and depending on the mode of operation in which eachintegrated circuit is placed. The parameter setting of the first andsecond laws of correspondence of the interface for external events 5 andof the interface for internal events 7 is carried out by the user insuch a manner as to specify for each control circuit 6 a, 6 b, 6 c whichevent, external or internal, is to be transmitted by the interface forexternal events 5 or the interface for internal events 7 so as totrigger the delivery of a signal for activation of tasks by the controlcircuit 6 a, 6 b, 6 c.

In emulation mode, in order to take into account all of the eventsrelating to the tasks of the electronic appliance APP, the outputs S18,S28, S38 of the output interface 8 and the outputs S14, S24 of the inputinterface 4 are respectively coupled to a second input E15 and a thirdbus input E35 of the interface for external events 5. Thus, thegeneration of a signal for activation of tasks by the input interface 4or the output interface 8 may be correctly interpreted by the interfacefor external events 5 and a corresponding first event signal can bedelivered to the control circuits 6 a, 6 b, 6 c. The control circuits 6a, 6 b, 6 c can thus take into account this first event signal in orderto generate, where required, another task activation signal.

In the embodiment illustrated in the single figure, the device 1furthermore comprises an additional control circuit 9 having two modesof operation and comprising two bus inputs E19, E29 respectively coupledto the outputs S17, S27, S37 of the interface for internal events 7 andto the outputs S15, S25, S35 of the interface for external events 5 andan output S19.

The first mode of operation of the additional control circuit 9 isconfigured for transforming a first or second event signal received onone of the two bus inputs E19, E29 into a corresponding task activationsignal and for delivering it via its output S19 to a circuit 13 of theelectronic appliance APP, without going via the output interface 8,depending on the signals delivered by the interface for external events5 and/or the interface for internal events 7.

The coupling of the outputs S18, S28, S38 of the output interface 8 andof the outputs S14, S24 of the input interface 4 at the input of theinterface for external events 5 allows all of the events relating to thetasks of the electronic appliance APP to be taken into account for theoperation of the additional control circuit 9 in its first mode ofoperation. Thus, the generation of a task activation signal by the inputinterface 4 or the output interface 8 can be correctly interpreted bythe interface for external events 5 and a first event signal can bedelivered to the additional control circuit 9 in order to be transformedinto another associated task activation signal.

The additional control circuit 9 thus allows the device 1 to control thecircuits of the electronic appliance APP which need a start signal andnotably those not communicating with the memory access controller 3.

The interface for internal events 7 furthermore comprises an additionalinput E37 coupled to the output S19 of the additional control circuit 9so as to furthermore take into account the events relating to thesignals delivered by the additional control circuit 9. The second law ofcorrespondence is programmed to take into account the signals receivedon the additional input E37.

The additional control circuit 9 furthermore incorporates a module 91for receiving a signal confirming reception of the transmitted signalwhich thus allows it to be verified that the circuit 13 coupled at theoutput of the additional control circuit 9 has indeed received the taskactivation signal delivered by the latter.

The module 91 for receiving a signal confirming reception is coupled tothe inputs E19, E29 of the additional control circuit 9. The receivermodule 91 is configured for detecting the reception on the inputs E19,E29 of the additional control circuit 9 of the event corresponding tothe task activation signal previously by the additional control circuit9.

The additional control circuit 9 can format the signal delivered by theoutput S19 so that the latter is adapted for a correct interpretation bythe circuit 13.

In the second mode of operation of the additional control circuit 9, theadditional control circuit 9 operates in “by-pass” mode as a simpleelectrical connector, in other words it routes directly an eventreceived at the input of the additional control circuit 9 to the outputof the additional control circuit 9 without modifying the signal. Themode “by-pass” is useful for presenting any given event signal, arrivingon the inputs E15, E25, E35, E17, E37, E47, via a single output S19.

In order to go from the first to the second mode of operation and viceversa, the additional control circuit 9 comprises an operational modeselector 90.

The device 1 for synchronization of the tasks also comprises aninterrupt block 10 whose inputs are coupled to the outputs of thecontrol circuits 6 and to the output of the additional control circuit9. The interrupt block 10 is coupled at the output to a microprocessorof the electronic appliance APP.

The various circuits of the device 1 may be formed by algorithms forsynthesis of logic circuits and/or by software, such as for example theinterface for external events 5 and the interface for internal events 7.

The device for synchronization of the tasks of integrated circuitscoupled, for at least some of them, to a memory access controller thusallows data to be processed on the fly using an electronic architecture.

What is claimed is:
 1. An electronic device, designed to synchronizetasks of an electronic appliance that comprises at least one circuit anda memory access controller having a plurality of inputs, each inputbeing associated with a priority level, the electronic devicecomprising: a plurality of control circuits configured to receivesignals from events and, in response, to deliver response signals foractivation of tasks; a configurable interface for external eventsdesigned to receive first event signals from the at least one circuit ofthe electronic appliance and to route at least certain of these firstevent signals to corresponding control circuits as a function of a firstlaw of correspondence; and a configurable interface for internal eventsdesigned to receive second signals from events corresponding to signalsfor activation of tasks delivered by the control circuits and to routeat least certain of them to the control circuits as a function of asecond law of correspondence; the control circuits each comprising anoutput, the outputs being designed to be connected to the inputs of thememory access controller depending on a desired priority level for thetasks associated with the signals for activation of tasks delivered byeach of the control circuits.
 2. The electronic device according toclaim 1, further comprising an input interface configured to transmitsignals for activation of tasks generated by integrated circuits coupledto the memory access controller via the electronic device to at leastone control circuit of the plurality of control circuits, the at leastone control circuit having a first mode of operation in which thecontrol circuit transmits a task activation signal received uponreception of a first or second event signal, the integrated circuitsbeing coupled to at least one of the control circuits via the inputinterface depending on the desired priority level for the tasksassociated with the signals for activation of tasks delivered by theintegrated circuits.
 3. The electronic device according to claim 1,wherein the at least one control circuit has a second mode of operationin which the at least one control circuit generates and delivers a taskactivation signal upon reception of a first or second event signal. 4.The electronic device according to claim 1, wherein the at least onecontrol circuit has a third mode of operation in which the at least onecontrol circuit operates as a simple electrical connector.
 5. Theelectronic device according to claim 1, further comprising an inputinterface configured to transmit signals for activation of tasksgenerated by integrated circuits coupled to the memory access controllervia the electronic device to at least one of the control circuits;wherein the at least one control circuit has a first mode of operationin which the at least one control circuit transmits the task activationsignal received upon reception of a first or second event signal, theintegrated circuits being coupled to at least one of the controlcircuits via the input interface depending on the desired priority levelfor the tasks associated with the signals for activation of tasksdelivered by the integrated circuits; wherein the at least one controlcircuit has a second mode of operation in which the at least one controlcircuit generates and delivers a task activation signal upon receptionof a first or second event signal; and wherein the at least one controlcircuit has a third mode of operation in which the at least one controlcircuit operates as a simple electrical connector.
 6. The electronicdevice according to claim 5, wherein the at least one control circuitcomprises an operational mode selector capable of switching theoperation of the at least one control circuit between the first, thesecond and the third mode of operation.
 7. The electronic deviceaccording to claim 1, further comprising at least one additional controlcircuit configured to receive the first and second event signals, the atleast one additional control circuit having a first mode of operation inwhich the at least one additional control circuit transforms the firstor second event signal received into a corresponding task activationsignal and delivers it via an output to a circuit of the electronicappliance without going via an output interface.
 8. The electronicdevice according to claim 7, wherein the at least one additional controlcircuit also comprises a module to receive a signal confirming receptionof the task activation signals configured to detect the reception at theinput of the additional control circuit of the event corresponding tothe task activation signal previously generated by the additionalcontrol circuit.
 9. The electronic device according to claim 7, whereinthe at least one additional control circuit has a second mode ofoperation in which an additional control circuit operates as a simpleelectrical connector.
 10. The electronic device according to claim 9,wherein the at least one additional control circuit comprises anoperational mode selector capable of switching the operation of theadditional control circuit between the first mode of operation and asecond mode of operation.
 11. An electronic device, designed tosynchronize tasks of an electronic appliance that comprises at least onecircuit and a memory access controller having a plurality of inputs,each input being associated with a priority level, the electronic devicecomprising: control circuit means for receiving signals from events and,in response, for delivering response signals for activation of tasks;first interface means for receiving first event signals from the atleast one circuit of the electronic appliance and for routing at leastcertain of these first event signals to the control circuit means as afunction of a first law of correspondence; and second interface meansfor receiving second signals from events corresponding to signals foractivation of tasks delivered by the control circuit means and forrouting at least certain of them to the control circuit means as afunction of a second law of correspondence; the control circuit meanshaving outputs to connect to to the inputs of the memory accesscontroller depending on a desired priority level for the tasksassociated with the signals for activation of tasks delivered by each ofthe control circuits.
 12. An electronic appliance comprising: at leastone circuit; a memory access controller having a plurality of inputs,each being associated with a priority level; a plurality of controlcircuits configured to receive signals from events and, in response, todeliver response signals for activation of tasks; a configurableinterface for external events designed to receive first event signalsfrom the at least one circuit of the electronic appliance and to routeat least certain of these first event signals to corresponding controlcircuits as a function of a first law of correspondence; and aconfigurable interface for internal events designed to receive secondsignals from events corresponding to signals for activation of tasksdelivered by the control circuits and to route at least certain of themto the control circuits as a function of a second law of correspondence;the control circuits each comprising an output, the outputs beingconnected to the inputs of the memory access controller depending on adesired priority level for the tasks associated with the signals foractivation of tasks delivered by each of the control circuits.
 13. Theelectronic appliance according to claim 12, further comprising an inputinterface configured to transmit signals for activation of tasksgenerated by integrated circuits coupled to the memory access controllerto at least one control circuit of the plurality of control circuits,the at least one control circuit having a first mode of operation inwhich the control circuit transmits a task activation signal receivedupon reception of a first or second event signal, the integratedcircuits being coupled to at least one of the control circuits via theinput interface depending on the desired priority level for the tasksassociated with the signals for activation of tasks delivered by theintegrated circuits.
 14. The electronic appliance according to claim 12,wherein the at least one control circuit has a second mode of operationin which the at least one control circuit generates and delivers a taskactivation signal upon reception of a first or second event signal. 15.The electronic appliance according to claim 12, wherein the at least onecontrol circuit has a third mode of operation in which the at least onecontrol circuit operates as a simple electrical connector.
 16. Theelectronic appliance according to claim 12, further comprising an inputinterface configured to transmit signals for activation of tasksgenerated by integrated circuits coupled to the memory access controllerto at least one of the control circuits; wherein the at least onecontrol circuit has a first mode of operation in which the at least onecontrol circuit transmits the task activation signal received uponreception of a first or second event signal, the integrated circuitsbeing coupled to at least one of the control circuits via the inputinterface depending on the desired priority level for the tasksassociated with the signals for activation of tasks delivered by theintegrated circuits; wherein the at least one control circuit has asecond mode of operation in which the at least one control circuitgenerates and delivers a task activation signal upon reception of afirst or second event signal; wherein the at least one control circuithas a third mode of operation in which the at least one control circuitoperates as a simple electrical connector; and wherein the at least onecontrol circuit comprises an operational mode selector capable ofswitching the operation of the at least one control circuit between thefirst, the second and the third mode of operation.
 17. The electronicappliance according to claim 12, further comprising at least oneadditional control circuit configured to receive the first and secondevent signals, the at least one additional control circuit having afirst mode of operation in which the at least one additional controlcircuit transforms the first or second event signal received into acorresponding task activation signal and delivers it via an output to acircuit of the electronic appliance without going via an outputinterface.
 18. The electronic appliance according to claim 17, whereinthe at least one additional control circuit also comprises a module toreceive a signal confirming reception of the task activation signalsconfigured to detect the reception at the input of the additionalcontrol circuit of the event corresponding to the task activation signalpreviously generated by the additional control circuit.
 19. Theelectronic appliance according to claim 17, wherein the at least oneadditional control circuit has a second mode of operation in which anadditional control circuit operates as a simple electrical connector.20. The electronic appliance according to claim 19, wherein the at leastone additional control circuit comprises an operational mode selectorcapable of switching the operation of the additional control circuitbetween the first mode of operation and a second mode of operation.